Study on Yeast-Like symbionts of Hishimonous phycitis Distant (Hem.: Cicadellidae), vector of witches' broom disease of lime (WBDL)

عنوان دوره: دومین کنگره بین المللی حشره شناسی ایران

Phytoplasma associated with witches' broom disease of lime, Candidatus phytoplasma aurantifolia has been considered as the most important threat to lime and the other citrus trees in Iran and the other infected countries. This phytoplasma is transmitted to other plants by Hishimonus phycitis (Hem. Cicadellidae). Leafhoppers are associated with symbiotic microorganisms which provide them essential amino acids lacking in their diets. Yeast-like relationships with insects are known as common and obligate symbiotic relationship. In addition to providing nutrients, endosymbionts may play other roles such as detoxification of plant secondary metabolaites, resistance to pathogens and parasitoid and reproductive alternations. A new biological control method for vector born disease is known as “symbiotic control”. A prerequisite for the development of future strategies for the symbiotic control of insect pests and insect-vector competence is the identification of insect-associated yeast-like whose characteristics appear promising. In the current study, Yeast-like symbionts housed in this vector were investigated in insects collected from 12 districts of citrus orchards distributed in southern Iran. Population of insects were collected from Hormozgan, Kerman, Sistan Baluchestan and Fars provinces by a D-Vac and stored at -20 ºC up to the DNA extraction. Total DNA was extracted by an adjusted protocol from Reineke et al., 1988. PCR was conducted with specific primer sets targeting 18S rRNA of the symbionts used in previous studies for the other Cicadellids. Expected-specific amplified bands were electrophoresed, purified and sequenced. Sequences were edited by Seqman (DNA star) software and BLAST searched with the other nucleotides reported from the other arthropods deposited in NCBI. Results revealed that this vector harboured two yeast-like symbionts namely Hamiltonaphis styraci and Candida sp. with a similarity of (98-99%) to those reported from the other cicadellids. These results substantiate the association of these two endosymbiotic microbiota with H. phycitis which may suggest their ecological interactions. To establish any endosymbiotic relationship and probable interfering in pathogen transmission, further studies are needed.

Yeast-like symbionts؛ Hishimonus phycitis؛ symbiotic control؛ Hamiltonaphis styraci؛ Candida sp